What an Agent Skill actually is
A Skill is a folder containing instructions in a file called SKILL.md, plus any scripts, references or assets it needs. Your agent client reads the skill’s description, and when your request matches, it loads the instructions and follows them.
That is the whole format — which is why skills move between clients so easily, and why "installing" one is more like filing it than compiling it.
Where skills live (by client)
Each agent client looks in its own skills directory. The layout inside is always the same: a skills folder, one subfolder per skill, with SKILL.md one level down.
- Claude Code — a project-level .claude/skills folder, or ~/.claude/skills on your machine for personal skills
- Codex — your Codex skills folder (~/.codex/skills on most setups), same one-folder-per-skill layout
- Other clients (Cursor, Copilot, Windsurf and friends) — a skills directory defined by the client; check its docs for the exact path
- Everywhere — skills/<skill-name>/SKILL.md is the shape to match
The three-step install
The mechanics take a minute; the judgement is all in step one.
- Get the skill folder — download it from a marketplace or copy it from a repository
- Drop it into the skills directory for your client — the folder name becomes the skill name
- Reload the client and ask for the task the skill covers — a well-written description makes it activate when relevant
Common problems (and the fix)
Most install disappointments are mechanical, not conceptual. Run through this list before assuming the skill is broken:
- Skill never loads — usually one folder too shallow or too deep; SKILL.md must sit directly inside skills/<name>/
- Skill loads at the wrong time — tighten the description in SKILL.md so the client knows exactly when it applies
- Two skills fight over the same name — rename one folder; the folder name is the identity
- Scripts fail on permissions — check the executable bit, or run the skill from a terminal once
No-install route: run skills online
If file trees are not your idea of a good afternoon, Capafy AI runs skill-based agents for you. Every agent is a packaged Skill with a publisher, a price and reviews — sign in with Google, open an agent and press Run in the browser, on desktop or mobile. No APK, no skills directory, nothing to keep updated.
Browsing is free, many agents are free or come with a free trial, and paid agents show their price up front — which also makes the marketplace the fastest way to A/B a skill before installing it anywhere.
Updated October 2026. Facts checked against the live Capafy AI marketplace.
